Advanced sleep phase syndrome (ASPS) is a sleep
disorder in which patients feel very sleepy early in the evening (e.g.
18:00-19:00) and wake up very early in the night (e.g. midnight, 1:00,
etc.).

It is the opposite of delayed sleep phase
syndrome.

ASPS is frequently encountered in the elderly
and in post-menopausal women. It can be treated pharmacologically, with evening
bright lights, or behaviorally with chronotherapy or free-running sleep.

The information above is not intended
for and should not be used as a substitute for the diagnosis and/or treatment
by a licensed, qualified, health-care professional. This article is licensed
under the GNU Free Documentation
License. It incorporates material originating from the Wikipedia article
"Advanced
sleep phase syndrome".